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Chinese Physics B 2017年第6期26卷 22-30页

作者： m Eshghi H mehraban S m Ikhdair Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Faculty of Physics Semnan UniversitySemnanIran Department of Physics Faculty of ScienceAn-Najah National UniversityNablusWest BankPalestine Department of Electrical Engineering Near East UniversityNicosiaNorthern CyprusMersin 10Turkey

We solve the Schrodinger equation with a position-dependent mass（PDm） charged particle interacted via the superposition of the morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharonov–bohm（AB） flux fields. The nonrelativistic bound state energies together with their wave functions are calculated for two spatially-dependent mass distribution functions. We also study the thermal quantities of such a system. Further, the canonical formalism is used to compute various thermodynamic variables for second choosing mass by using the Gibbs formalism. We give plots for energy states as a function of various physical parameters. The behavior of the internal energy, specific heat, and entropy as functions of temperature and mass density parameter in the inverse-square mass case for different values of magnetic field are shown.

关键词： Schr?dinger equation morse-plus-Coulomb potentials position-dependent mass distribution functions perpendicular magnetic and Aharonov–bohm flux fields

Characteristics of Positive Ions in the Sheath Region of magnetized Collisional Electronegative Discharges

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Plasma Science and Technology 2014年第6期16卷 552-556页

作者： m.m.HATAmI A.R.NIKNAm Physics Department of K.N.Toosi University of Technology Laser-Plasma Research Institute of Shahid Beheshti University G.C.

A hydrodynamic model is used to investigate the characteristics of positive ions in the sheath region of a low-pressure magnetized electronegative discharge. Positive ions are modeled as a cold fluid, while the electron and negative ion density distributions obey the Boltzmann distribution with two different temperatures. By taking into account the ion-neutral collision effect in the sheath region and assuming that the momentum transfer cross section has a power law dependence on the velocity of positive ions, the sheath formation criterion （modified bohm＇s criterion） is derived and it is shown that there are specified maximum and minimum limits for the ion mach number m. Considering these two limits of m, the behaviors of electrostatic potential, charged particle density distributions and positive ion velocities in the sheath region are studied for different values of ion-neutral collision frequency.

关键词： electronegative plasma hydrodynamic model magnetized plasma sheath,bohm's criterion

Energy states of the Hulthen plus Coulomb-like potential with position-dependent mass function in external magnetic fields

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Chinese Physics B 2018年第2期27卷 234-238页

作者： m Eshghi R Sever S m Ikhdair Young Researchers and Elite Club Central Tehran Branch Islamic Azad University Department of Physics Middle East Technical University Department of Physics Faculty of Science An-Najah National University Department of Electrical Engineering Near East University

We need to solve a suitable exponential form of the position-dependent mass （PDm） Schr6dinger equation with a charged particle placed in the Hulthen plus Coulomb-like potential field and under the actions of the external magnetic and Aharonov-bohm （AB） flux fields. The bound state energies and their corresponding wave functions are calculated for the spatially-dependent mass distribution function of interest in physics. A few plots of some numerical results with respect to the energy are shown.

关键词： Schr6dinger equation Hulthen plus Coulomb-like potential position-dependent mass distributionfunctions perpendicular magnetic and Aharonov-bohm flux fields

Surface plasmon oscillations in a semi-bounded semiconductor plasma

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Plasma Science and Technology 2018年第2期20卷 76-81页

作者： m SHAHmANSOURI A P mISRA Department of Physics Faculty of ScienceArak University Department of mathematics Siksha BhavanaVisva-Bharati University

We study the dispersion properties of surface plasmon（SP） oscillations in a semi-bounded semiconductor plasma with the effects of the Coulomb exchange（CE） force associated with the spin polarization of electrons and holes as well as the effects of the Fermi degenerate pressure and the quantum bohm *** from a quantum hydrodynamic model coupled to the Poisson equation,we derive the general dispersion relation for surface plasma *** results in this context are *** dispersion properties of the surface waves are analyzed in some particular cases of interest and the relative influence of the quantum forces on these waves are also studied for a nano-sized Ga As semiconductor *** is found that the CE effects significantly modify the behaviors of the SP *** present results are applicable to understand the propagation characteristics of surface waves in solid density plasmas.

关键词： surface plasmon oscillations semiconductor plasma semi-bounded plasma

Influence of Discharge Voltage on Charged Particles in a multi-Dipole Device in the Presence of an Ion Collecting Surface

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Chinese Physics Letters 2013年第1期30卷 122-126页

作者： m.K.mishra A.Phukan m.Chakraborty Department of Physics Baosi Banikanta Kakati CollegeNagaonBarpetaAssam-781311India Department of Physics Madhabdev CollegeNarayanpurLakhimpurAssam-784164India Centre of Plasma Physics-Institute for Plasma Research TepesiaSonapurAssam-782402India

The influence of discharge voltage on ion collecting surfaces in the form of a metal plate and a mesh grid is investigated in a multi-dipole *** the experiment,a solid metal plate and a mesh grid are placed alternately at one end of the multi-dipole *** is seen that except for high negative bias,the ion space charge layer in front of the grid gets depleted with the increase in discharge voltage whereas it gets thickened in front of the *** is also observed that the electron loss at the cusp(anode current)changes accordingly in both the *** increase in discharge voltage can enhance the bohm speed of ions towards the ion collecting ***,the negative potential applied to the ion collecting surfaces lowers the bulk plasma potential,which in turn affects the anode current.

关键词： dipole anode thick

Effects of external fields on a two-dimensional Klein-Gordon particle under pseudo-harmonic oscillator interaction

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Chinese Physics B 2012年第11期21卷 68-73页

作者： Sameer m.Ikhdair majid Hamzavi Physics Department Near East University Department of Basic Sciences Shahrood BranchIslamic Azad University

We study the effects of the perpendicular magnetic and Aharonov-bohm （AB） flux fields on the energy levels of a two-dimensional （2D） Klein Gordon （KG） particle subjected to an equal scalar and vector pseudo-harmonic oscillator （PHO）. We calculate the exact energy eigenvalues and normalized wave functions in terms of chemical potential param- eter, magnetic field strength, AB flux field, and magnetic quantum number by means of the Nikiforov Uvarov （NU） method. The non-relativistic limit, PHO, and harmonic oscillator solutions in the existence and absence of external fields are also obtained.

关键词： Klein-Gordon equation two-dimensional pseudo-harmonic oscillator (PHO) potential,magnetic and Aharonov-bohm (AB) flux fields Nikiforov-Uvarov method

Relativistic Landau quantization in the spiral dislocation spacetime

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Communications in Theoretical Physics 2021年第2期73卷 68-72页

作者： A V D m maia K Bakke Departamento de Fisica Universijade Federal da ParaibaCaixa Postal 500858051-900Joao PessoaPBBrazil

We analyse the interaction of a relativistic electron with a uniform magnetic field in the spiral dislocation *** show that analytical solutions to the Dirac equation can be obtained,where the spectrum of energy corresponds to the relativistic Landau *** also analyse the influence of the spiral dislocation on the relativistic Landau levels by showing that there exists an analogue of the Aharonov–bohm effect for bound states.

关键词： spiral dislocation spacetime relativistic Landau quantization Aharonov-bohm effect relativistic wave equations Dirac equation

Energy transport for ion acoustic waves in a spin polarized quantum plasma

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Communications in Theoretical Physics 2020年第1期72卷 124-129页

作者： m Ayub Z Iqbal H A Shah G murtaza Salam Chair Department of PhysicsG.C.UniversityKatchery RoadLahore 54000Pakistan Department of Physics G.C.UniversityKatchery RoadLahore 54000Pakistan Department of Physics Mirpur University of Science and TechnologyMirpur-10250(AJK)Pakistan

The separate spin evolution quantum hydrodynamics(SSE-QHD)model is used to investigate the energy behavior for ion acoustic waves in degenerate quantum *** results show that the energy flow speed decreases with spin polarization *** is also shown that it decreases with the increasing rate up to a certain range of wave number and then it goes to zero *** is observed that bohm potential suppresses the energy flow *** is also noticed that the energy flow speed deviates from the group velocity even in the absence of bohm potential ***,the contribution of of bohm poential effect in spin polarized plasma reduces the extent of deviation.

关键词： spin polarization quantum plasma ion acoustic wave energy flow speed

Influence of Auxiliary Equation on Wave Functions for Time-Dependent Pauli Equation in Presence of Aharonov-bohm Effect

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Communications in Theoretical Physics 2009年第5期51卷 803-810页

作者： m.maamache C.Lahoulou Y.Saadi Laboratoire

Invariant operator method for discrete or continuous spectrum eigenvalue and unitary transformation approach are employed to study the two-dimensional time-dependent Pauli equation in presence of the Aharonov-bohm effect （AB） and external scalar potential. For the spin particles the problem with the magnetic field is that it introduces a singularity into wave equation at the origin. A physical motivation is to replace the zero radius flux tube by one of radius R, with the additional condition that the magnetic field be confined to the surface of the tube, and then taking the limit R → 0 at the end of the computations. We point that the invariant operator must contain the step function θ（r - R）. Consequently, the problem becomes more complicated. In order to avoid this dimculty, we replace the radius R by ρ（t）R, where ρ（t） is a positive time-dependent function. Then at the end of calculations we take the limit R →0. The qualitative properties for the invariant operator spectrum are described separately for the different values of the parameter C appearing in the nonlinear auxiliary equation satisfied by p（t）, i.e., C 〉 0, C = 0, and C 〈0. Following the C＇s values the spectrum of quantum states is discrete （C 〉 0） or continuous （C ≤ 0）.

关键词： time-dependent systems invariant theory Aharonov-bohm effect Pauli equation

肺泡复张策略复合高水平呼气末正压通气不影响血容量充足的病态肥胖患者的血流动力学

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麻醉与镇痛 2011年第3期7卷 66-69页

作者： Stephan H. bohm, mD Oliver C. Thamm, mD Alexandra von Sandersleben, mD Katrin Bangert, mD Thomas E. Langwieler, mD Gerardo Tusman, mD Tim G. Strate, mD, PhD Thomas G. Standl, mD, PhD 邓希锦(译) Clinics of Anesthesiology Hospital Privado de Comunidad Mar del Plata Argentina General Visceral and Thoracic Surgery University Hospital Hamburg-Eppendorf Germany Hospital Privado de Comunidad Mar del Plata Argentina Department of Anesthesiology Hospital Privado de Comunidad Mar del Plata Argentina 不详

我们观察了20例血容量充足，准备行腹腔镜手术的病态肥胖（体重指数为50±9kg/m^2）患者，评估肺泡复张策略复合高水平呼气末正压通气（posidveend-expiratorypressure，PEEP）对其血流动力学的影响。肺泡复张策略是在有气腹和无气腹的... 详细信息

我们观察了20例血容量充足，准备行腹腔镜手术的病态肥胖（体重指数为50±9kg/m^2）患者，评估肺泡复张策略复合高水平呼气末正压通气（posidveend-expiratorypressure，PEEP）对其血流动力学的影响。肺泡复张策略是在有气腹和无气腹的情况下序贯进行，将PEEP水平逐渐升高，使平台压达到50—60cmH2O，呼吸10次／分，然后将PEEP水平逐渐降低。通过体循环和肺动脉导管的监测，没有发现肺泡复张及高水平PEEP对血流动力学产生显著的影响。经食管超声心动图显示左室舒张末期面积未发生变化，也无局部室壁运动异常的迹象。

关键词：呼气末正压通气血流动力学肥胖患者病态肥胖 P水平血容量肺泡复合